<style>
    body {
        overflow: hidden;
    }

    body * {
        -webkit-touch-callout: none;
        -webkit-user-select: none;
        -moz-user-select: none;
        -ms-user-select: none;
        user-select: none;
    }

    .map {
        position: absolute;
        top: 0;
        bottom: 0;
        width: 100%;
    }
</style>
<script src="https://api.mapbox.com/mapbox-gl-js/plugins/mapbox-gl-compare/v0.4.0/mapbox-gl-compare.js"></script>
<link
    rel="stylesheet"
    href="https://api.mapbox.com/mapbox-gl-js/plugins/mapbox-gl-compare/v0.4.0/mapbox-gl-compare.css"
    type="text/css"
/>
<div id="comparison-container">
    <div id="before" class="map"></div>
    <div id="after" class="map"></div>
</div>
<script>
    var beforeMap = new mapboxgl.Map({
        container: 'before',
        style: 'mapbox://styles/mapbox/light-v10',
        center: [0, 0],
        zoom: 0
    });

    var afterMap = new mapboxgl.Map({
        container: 'after',
        style: 'mapbox://styles/mapbox/dark-v10',
        center: [0, 0],
        zoom: 0
    });

    // A selector or reference to HTML element
    var container = '#comparison-container';

    var map = new mapboxgl.Compare(beforeMap, afterMap, container, {
        // Set this to enable comparing two maps by mouse movement:
        // mousemove: true
    });
</script>
